1. Sulfur dyes;Croissant,2000
2. Novel dyes and commercial forms;Shankarling;Colourage,1997
3. Optimization of the synthesis of a water soluble sulfur black dye;Wang;Dyes Pigments,2001
4. Sulfur dyes – chemical constitution;Heid,2003
5. P.N. Cote, X. Lan, A.I. Shakhnovich, M.J. Domingo, Sulfur dyes, US Patent No. 5961670, 1999.